Inflatable mattress

ABSTRACT

The document concerns inflatable mattresses, in particular non-durable, inflatable mattresses. The inflatable mattress can be simply constructed from flexible sheet materials internally joined to form inflatable chambers.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates in general to inflatable mattresses, in particular non-durable, preferably disposable inflatable mattresses, particularly single-use inflatable mattresses.

Further aspects of the invention can concern a method of making the inflatable mattress; and a method of disposing of, preferably recycling, the inflatable mattress.

Description of the Related Art

Inflatable mattresses of various sizes and shapes are well known and are used in a variety of situations when temporary bedding is desired. Uses may include recreational camping, such as during vacations or at outdoor festivals; and/or provision of emergency bedding, in the event of displacement of persons from their normal residence, such as in refugee camps.

Common inflatable mattresses are typically made with the aim of long-term reusability. Such traditional inflatable mattresses can be time consuming and complex to inflate; heavy and inconvenient to transport, either as a user or a seller; and expensive and difficult to produce and dispose of, making them unsuitable for short-term use or single use applications.

For example, it is known that relatively inexpensive forms of inflatable mattresses are often used singularly, e.g. at festivals. However, these conventional inexpensive camping mattresses have not been explicitly designed for single-use purposes and are simply low-quality versions. These low-quality mattresses can readily break and become unusable, they are also of relatively low cost, and so users tend to discard them on festival campgrounds. These discarded mattresses can form a major waste problem because although cheap and of low quality, they contain mixed type, durable plastics. In addition, although they are inexpensive and a low-quality version of conventional mattresses, the complexity of such conventional constructions, as well as the production methods for the materials, can still result in laborious and overly expensive manufacture, distribution, and a higher than desired environmental impact.

Examples of inflatable mattresses are known in prior patent publications. Such mattresses may typically comprise a single inflated chamber that is inflated and deflated through a single valve. For example, EP3245905A1 describes an inflatable mattress comprised of layers connected to form an inflatable chamber with a valve for both inflation and deflation, allowing reuse. The materials used are substantial, provide for reuse and are thus complex for manufacture, heavy for transport and not easily disposed of or recycled.

A further problem with such conventional inflatable mattresses is that if a puncture occurs, the whole mattress will deflate. Providing individually inflated chambers, sealed from one another is not common because this complicates inflation and deflation for a user and requires a multitude of two-way valves, increasing expense and weight.

U.S. Pat. No. 5,303,435 discusses a self-inflating mattress. That mattress is provided with self-inflating sections that individually inflate under influence of a self-expanding, internally contained open cell urethane foam. The mattress is made substantial to be reused by backpackers. The materials and construction of that mattress may have a negative impact on its disposability and/or recyclability.

Other mattresses with a multiplicity of inflatable chambers operated independently can be found in medical applications. US2011/0094040A1 discusses a mattress in which inflatable chambers are selectively and independently inflated and deflated to vary pressure on an occupant. The system is clearly highly complex, expensive, and requires an advanced control system.

A further example of an inflatable mattress is discussed in patent publication WO2015/010153. That mattress has an upper sheet of material a lower sheet of material and a layer of insulating material internal of the upper and lower sheets. Again, the materials and construction of such an inflatable mattress may have a negative impact on its disposability and/or recyclability.

An inflatable mattress is also discussed in WO2018/162715, which inflatable mattress provides many advantages, but which may still be improved upon for recyclability, comfort, ease of use and economy.

A commercially available inflatable, disposable mattress has also been made available, known as the ‘psssh airbed’, improvements in recyclability, comfort, ease of use and economy are, however, needed.

Other types of camping mattresses are also known. A common type being closed-cell foam rollable mattresses, such as expanded polyurethane foam. Such mattresses do not suffer from the problem of puncturing but are difficult to dispose of and continue to occupy a great deal of volume after use.

There remains a need for an improved inflatable mattress, which is preferably one or more of: easy to inflate; easy to deflate; easy to dispose of, e.g. by recycling or destruction; lightweight; secure; compact in a pre-inflation state; comfortable for a user; low cost in material content and manufacturability; readily manufactured on a large scale; and of low environmental impact compared to at least some prior art inflatable mattresses.

The Invention

In general, the invention concerns an inflatable mattress.

In a first aspect of the invention there is provided an inflatable mattress comprising:

-   -   a flexible sheet of material encompassing an inflatable interior         volume, the flexible sheet having an upper external surface, an         upper internal surface, a lower internal surface and a lower         external surface; wherein     -   the upper internal surface is joined to the lower internal         surface in a pattern of join lines forming a plurality of         inflatable chambers, each chamber having an inflation port,         wherein said inflation ports are arranged to be permanently         sealed once inflated.

Making the inflatable mattress from flexible sheet material having inflated chambers allows the use of minimal materials and highly efficient manufacturing. In addition, the disposal by recycling or destruction of flexible, single-use, sheet materials can be less complex and more effective and efficient than recycling or disposal of more durable multi-use materials (i.e. intended for multiple deflation and re-inflation uses).

The inflatable mattress may be provided to a user in an uninflated state. The mattress can then be inflated with an inflating fluid, such as a gas (e.g. air or N₂), using e.g. a manual or powered pump, or from a compressed gas cylinder.

The uninflated mattress may, for example, be provided as a rolled or folded discreet package. Alternatively, a roll or other collection comprising a plurality of overlapping or joined uninflated mattresses may be provided and dispensed from the roll to a group of users. The individual mattresses may be attached along frangible joins at their ends or along their edges, so that they can be torn or separated from one another. A roll or collection of inflatable mattresses may comprise 20 or more inflatable mattresses, preferably 30 or more, preferably up to 100. While greater numbers of mattresses per roll may be provided, this may become too heavy of convenient manual handling. For manual handling the roll of mattresses may have a weight of 15 kg or less, more preferably 10 kg or less. If mechanical lifting is used, the roll may comprise a greater number of mattresses, for example 300 or more.

The mattress functions primarily to provide physical support and thermal insulation for a user, for example during sleeping.

In one alternative, said inflatable chambers are provided with one-way (gas) valves for inflation of said inflatable chambers. The one-way valves preferably prevent non-destructive deflation.

Mattress Dimensions

In plan view the inflatable mattress is preferably substantially rectangular.

An inflatable mattress has a length. The length of the mattress is preferably from about 100 cm to about 500 cm, more preferably from about 150 cm to about 300 cm, still more preferably from about 180 cm to about 250 cm, and most preferably from about 190 cm to about 220 cm.

The inflatable mattress has a width, which is the lateral distance at right angles to the length. In the case that the width of the mattress varies along its length, the inflatable mattress width refers to the average width. An inflatable mattress has a mid-point width, which is the width taken at the mid-point of the length. The width and/or midpoint width and/or end widths are preferably from about 50 cm to about 250 cm, more preferably from about 70 cm to about 220 cm, still more preferably from about 80 cm to about 210 cm, and most preferably from about 90 cm to about 200 cm.

Preferably the inflatable mattress is sized as one of, a one-person mattress (e.g. 90 cm×200-210 cm), or a two-person mattress, a three-quarter size mattress (e.g. 140 cm×200-210 cm) or a double size mattress (e.g. any of 160 cm×200-210 cm; 180 cm×200-210 cm; or 200 cm×200-210 cm).

For a one-person mattress the width and/or midpoint width are preferably from about 50 cm to about 100 cm, more preferably from about 60 cm to about 90 cm.

For a two-person mattress, the width and/or midpoint width is preferably from about 100 cm to about 220 cm, preferably from about 120 cm to about 200 cm, more preferably from 160 cm to 200 cm.

Inflated sealed chambers of the mattress are preferably from 2 to 20 cm in height, more preferably 5 to 15 cm.

Inflatable Chambers

The inflatable mattress is provided with inflatable chambers. The chambers are formed by joining together the inner upper and inner lower surfaces of the flexible sheet, at a periphery about a then closed chamber. The term “closed chamber” refers to a physical barrier surrounding an inflatable volume, for example, such as an inflatable cell, wherein an inflating material can be kept within the volume to internally pressurize the physical barrier, that is, to inflate the chamber. The chambers are in this manner inflatable cells. Preferably the chambers comprise an inflatable volume encompassed by the flexible sheet, one or more peripheral joins of the upper inner surface and the lower inner surface.

Preferably the chambers are permanently sealed about their full periphery. Sealing is preferably done by heat sealing, conductive sealing, impulse sealing, ultrasonic sealing, welding, crimping, bonding, adhering, and combinations of any of these. Heat sealing is preferred. Optionally one or more one-way valves may also be provided, although this may be less preferred because of a higher risk of leakage if the one-way valves are not sealed.

The flexible sheet may comprise a tube of flexible material that is sealed to itself to form said chambers. The flexible sheet may alternatively comprise a two-dimensional sheet of flexible material folded upon itself to form upper and lower surfaces, the inner surfaces (upper inner surface and lower inner surface) of which are then joined to form the chambers. The flexible sheet may alternatively comprise distinct first and second flexible sheets that are aligned opposite one another and joined together to form the chambers.

The term “closed” encompasses the inclusion of a one-way or two-way valve that is configured to hinder, restrict or substantially prevent loss of inflation material during the use of the inflatable mattress, such that a closed chamber remains inflated during use to provide support to a user's weight.

The term “sealed” refers to a permanent, fluid-tight, preferably gas-tight seal. It does not encompass a one-way or two-way valve unless that valve has been permanently sealed such that it is fluid tight. It is preferred that the chambers are sealed closed as this provides a robust, leak-resistant inflated mattress. Each chamber is preferably sealed about its the full periphery once inflated.

The chambers are preferably elongate, that is, they have length.

The chambers may be disposed transverse of the mattress or longitudinally. Preferably the chambers are transverse. This can provide most comfort in the event of a chamber being punctured and may also allow easy creation of a headrest or pillow by folding or rolling of an end of the mattress.

The chambers may be disposed side by side, in parallel, wherein, in various embodiments, part, parts, or about all, or approximately all, or substantially all, or nearly all, or all of some or all of the chambers can be partly or fully in contact with each other, partly or fully directly connected to each other, and/or partly or fully joined to each other along side-joins.

The periphery of the chambers is preferably straight, but other forms, such as sinusoidal or wavy etc. are also possible.

Adjacent chambers may be sealed from one another, at least once inflated, to substantially prevent flow of an inflating material between them. This may help to maintain comfort in the event one chamber is punctured, and also aids in ensuring a generally even spread of support for a user's body across the mattress.

Adjacent chambers may be in restricted fluid-communication for passage of inflating material therebetween. In this respect, any openings or ports are preferably sealed once inflated. Alternatively, one-way and/or two-way valves may be provided between adjacent structural support chambers. If two way-valves are provided, these are preferably sealed after inflation. If one-way valves are provided, these are one-way for inflation, substantially preventing (non-destructive) deflation.

Sealing between adjacent inflatable chambers can help to prevent loss of structural integrity of the mattress in the event of unintended puncture of one or more of the individual chambers.

In the uninflated state (for example, pre-inflated or deflated) the structural support chambers are unfilled or unexpanded, so that the enveloping flexible sheet is not held in tension by an internal pressure. The chambers, and hence also the mattress, in this state are flexible, and occupy minimal space. This allows for simple packaging and transportation of the mattress in an uninflated state.

To inflate the mattress, the chambers can be inflated with an inflating material. Substantially filling the chambers with an inflating material creates tension in the flexible sheet imparting rigidity thereto. The emergent rigidity in the inflated chambers forms a support structure upon which a user can recline.

In a preferred example, each chamber is provided with at least one inflation port located at a proximal end of each chamber. The inflation ports are preferably narrower, e.g. have a smaller open cross-sectional area, than a body of the associated inflatable chamber. The port may be provided as at least one change in chamber width, preferably at an open end of an uninflated chamber. A change in the open cross-sectional area may be achieved by bringing one or more outer walls of a chamber toward one another to narrow the width, or by including an inter-chamber join forming an island in an open end of a chamber.

Inflating materials include fluids e.g. liquids and gases, and most preferably comprise gas (e.g. air, N₂, inert gases, or mixtures thereof). The chambers are preferably gas inflated. The gas inflation creates an internal pressure in the closed chambers. Alternative inflation materials that may be used include foams, gels, or liquids, however, for cost and weight purposes, these alternatives are less preferred. Preferably, the chambers are not inflated by and/or do not contain foams, in particular self-inflating foams or open-cell foams.

The chamber internal pressure when inflated is greater than ambient pressure. Preferably the internal pressure is greater than atmospheric pressure, preferably an absolute pressure of greater than 1 bar, preferably from 1.1 bar to 4 bar, more preferably from 1.3 bar to 3 bar, more preferably from 1.5 bar to 2 bar.

The pressure may preferably be a gauge pressure of from 0.1 to 3 bar, preferably 0.4 to 2 bar, preferably 2 bar or less than 2 bar, possibly 0.5 bar or less.

The chambers preferably comprise opposed end-joins between the upper and lower inner surfaces of the flexible sheet defining the longitudinal outer ends of the chambers. The closed chambers preferably comprise opposed side-joins between upper and lower inner surfaces of the flexible sheet, extending between the end-joins to enclose the inflatable volume.

In some embodiments, one or more chambers may be provided in series, the series of chambers extend in the width of the mattress. The individual chambers in series are preferably separated from one another by end-wall joins.

Preferably the mattress is provided with chambers over its full width.

Most preferably chambers adjacent in the mattress share one or more join lines.

In preferred embodiments the mattress comprises from 5 to 50 adjacent chambers in its length, more preferably from 10 to 40, more preferably from 15 to 30, and most preferably from 20 to 30 adjacent chambers in its length. It is believed that in general an increased number of adjacent chambers may improve comfort, yet fewer chambers makes use of less material. Comfort may be optimized by providing a balance between a small chamber cross-section that might result in a user contacting the ground unless the chamber is inflated to be very hard, and a large chamber cross-section such that the surface is no longer comfortably planar for a user to recline on.

In some embodiments parallel chambers are provided with a non-inflated flexible portion between. The non-inflated, flexible portion may be a non-inflated volume between the first and second flexible sheets but is preferably a shared end-join between the parallel chambers. The flexible portion may act as a line of flexure, such as a (living)hinge, between the (semi-)rigid inflated chambers. Inclusion of one or more lines of flexure can allow a number of inflated chambers to be rolled back upon the mattress body to form a headrest or pillow.

In some embodiments, the adjacent chambers are complementary in shape along elongate boundaries between them. For example, straight edges or a meander or wave form of a first chamber may be complementary with a meander or wave form of a directly, adjacent chamber. The line of the adjacent sides may in this way nest, mesh, and/or conform to one another.

In any of the embodiments discussed, the structural chambers may be generally cylindrical, having a lateral cross-section that is generally elliptical, oval or substantially circular, when inflated. Such a lateral cross-section can result from the construction of the chambers from directly joined inner surfaces of the flexible sheet. This is distinct from closed chambers that may be formed of three, four or more panels e.g. having upper and lower panels indirectly attached by intermediate side-walls, which take on generally multisided cross-sections, having corners e.g. square, when inflated.

Preferably the closed chambers are be sealed once inflated, such that deflation is only possible by destructive measures. Sealing is preferably done by heat sealing, conductive sealing, impulse sealing, ultrasonic sealing, welding, crimping, bonding, adhering, and combinations of any of these. Heat sealing is preferred. Alternatively, closing of the chambers may be achieved by use of one or more one-way valves allowing inflation but not deflation, such valves may be sealed after inflation to reduce or prevent leakage.

The air chambers are preferably free of foams, such as open-cell and/or self-expanding foams as found in come prior art mattresses that self-inflate. Such foams are voluminous even when compressed, increase costs, may have unwanted environmental impact during manufacture, and are detrimental to recyclability.

Flexible Material

The flexible material may comprise a tube of flexible material that is joined or sealed to itself to form the inflatable chambers. The flexible sheet may alternatively comprise a two-dimensional sheet of flexible material folded upon itself to form upper and lower surfaces, the inner surfaces (upper inner surface and lower inner surface) of which are then joined to form the chambers. The flexible sheet may alternatively comprise distinct first and second flexible sheets that are aligned opposite one another and joined together to form the chambers. The sheets may also be comprised of strips, patches or other units of sheet material, joined together in a plane.

In the present application the terms “sealed”, “joined” and “join” in reference to the connection of the sheet's internal surfaces refers to surfaces being joined directly to one another. This refers to a configuration wherein the surfaces are attached to each other without intermediate elements between, except for optional means of attachment, e.g. adhesive or a heat weld. For example, joining of the surfaces is done without any dimensionally substantial components, such as intermediate sidewalls. The surfaces are directly joined to one another rather than indirectly connected.

Joining of the inner surfaces to one another can be done using any kind of joining technique, preferable examples include sealing (e.g. heat sealing, conductive sealing, impulse sealing, ultrasonic sealing, etc.), welding, crimping, bonding, adhering, and combinations of any of these. Heat sealing is preferred.

As used herein, the term “indirectly connected” refers to a configuration wherein elements are attached to each other with one or more intermediate elements therebetween.

The flexible materials of the mattress are easily deformable, sheet-like material, having a flexibility factor within the range of 1,000-2,500,000 N/m, preferably from 1,000 to 1,500,000 N/m, more preferably from 1,500 to 1,000,000 N/m, still more preferably from 2,500 to 800,000 N/m, still more preferably from 5,000 to 700,000 N/m, still more preferably from 10,000 to 600,000 N/m, still more preferably from 15,000 to 500,000 N/m, still more preferably from 20,000 to 400,000 N/m, still more preferably from 25,000 to 300,000 N/m, still more preferably from 30,000 to 200,000 N/m, still more preferably from 35,000 to 100,000 N/m, still more preferably from 40,000 to 90,000 N/m, most preferably from 45,000 to 85,000 N/m.

The flexibility factor refers to a material parameter for a thin, easily deformable, sheet-like material, wherein the parameter is measured in Newtons per meter, and the flexibility factor is equal to the product of the value for the Young's modulus of the material (measured in Pascals) and the value for the thickness of the material (measured in meters).

The flexible sheets may comprise one or more of any of the following materials: films (such as plastic films), elastomers, foamed sheets, foils, fabrics (including wovens and nonwovens), biosourced materials, and papers, in any configuration, as separate material(s), or as layer(s) of a laminate, or as part(s) of a composite material. In various embodiments, part, parts, or all of a flexible material can be coated or uncoated, treated or untreated, processed or unprocessed, to give desired characteristics such as gas impermeability, water resistance/proofing etc. In various embodiments, parts, parts, or all of a flexible material can made of sustainable, bio-sourced, recycled, recyclable, and/or biodegradable material.

The flexible sheets may be made from a variety of materials that can confine materials used to inflate the inflated structural chambers of the mattress, for example gases, in particular air or N₂.

Exemplary materials include, without limitation, polyethylene (homopolymers, such as low density polyethylene (LDPE) and high density polyethylene (HDPE); and copolymers, such as ionomers, EVA, EMA, ethylene/alpha-olefin copolymers), polypropylene (homopolymers and copolymers, such as propylene/ethylene copolymer), polylactic acid, polyethylene terephthalate, polyethylene furanoate, polyester, nylon, polyvinyl chloride, polystyrenes, polyamides, polycarbonates, and the like. LDPE is a preferred construction material. Ethylene vinyl alcohol (EVOH) and polyamides (especially nylon) are preferred gas barrier materials.

Without wishing to be bound by theory, it is believed that the use of LDPE as flexible material, either alone, in a blend, or in a laminate, provides improved comfort for a user. For example, it is believed that LDPE has low levels of noise generation (crackling) upon physical contact from user movement, especially when compared to HDPE. This may be important in the context of providing good rest.

The flexible material may be made by any known extrusion process by melting the component polymer(s) and extruding, coextruding, or extrusion-coating them through one or more flat or annular dies, in particular tubular films may be obtained by film blowing (blown film extrusion).

Polymer sheets that are susceptible to heat sealing techniques are preferred for ease of manufacturing and construction. For example, continuous webs of flexible material can be heat sealed to one another in various patterns to form the closed chambers discussed above. Polyethylene is susceptible to heat sealing.

Further exemplary materials may be sustainable, bio-sourced, recycled, recyclable, and/or biodegradable materials. For example, low density polyethylene (LDPE), which can be recycled into LDPE resin pellets, and then used to form new products, saving energy and mineral oil resources.

As used herein, the prefix “bio-” is used to designate a material that has been derived from a renewable resource. Nonlimiting examples of renewable resources include plants (e.g., sugar cane, beets, corn, potatoes, citrus fruit, woody plants, lignocellulosics, hemicellulosics, and cellulosic waste), animals, fish, bacteria, fungi, and forestry products. Natural resources such as crude oil, coal, natural gas, and peat are not renewable resources.

Nonlimiting examples of renewable polymers include polymers directly produced from organisms, such as polyhydroxyalkanoates and bacterial cellulose; polymers extracted from plants and biomass, such as polysaccharides and derivatives thereof (e.g., gums, cellulose, cellulose esters, chitin, chitosan, starch, chemically modified starch), proteins (e.g., zein, whey, gluten, collagen), lipids, lignins, and natural rubber; and current polymers derived from naturally sourced monomers and derivatives, such as bio-polyethylene, bio-polypropylene, polytrimethylene terephthalate, polylactic acid, NYLON 11, alkyd resins, succinic acid-based polyesters, and bio-polyethylene terephthalate.

The flexible material of the mattress may comprise mixtures of different polymers, including mixtures of polymers from both renewable and non-renewable resources.

The flexible material preferably has a basis weight of from 10 to 2,000 gsm, preferably from 15 to 1200 gsm, more preferably 20 to 800 gsm, still more preferably 25 to 600 gsm, and most preferably or 30 to 400 gsm. The term “basis weight” refers to a measure of mass per area, in units of grams per square meter (gsm).

The flexible material may have a thickness such that it is compliant and readily deformable for packing, handling, inflation, destruction, transportation, and disposal. In some embodiments the thickness of the upper side of the mattress and under side of the mattress are approximately the same. In other embodiments, the thickness of the flexible material forming the underside of the mattress may be greater than or less than the thickness of the flexible material forming the upper side of the mattress. The underside flexible material may be thicker to increase puncture resistance.

The flexible material preferably has a thickness of from 10 to 1000 micrometers, more preferably from 15 to 800 micrometers, more preferably from 20 to 600 micrometers, more preferably from 25 to 400 micrometers, more preferably from 30 to 200 micrometers, more preferably from 30 to 250 micrometers, more preferably from 30 to 200 micrometers, and most preferably from 30 to 100 micrometers.

It is preferable that the gas barrier properties of the flexible material are suitably high to contain pressurized inflation gas (typically air) for the foreseen use of the mattress.

It is preferable that a mattress inflated to an absolute pressure of 1.3 bar (preferably to 2 bar or more preferably to 3 bar) with nitrogen, at 25° C. and at atmospheric pressure maintain at least 95% of its initial pressure when held at those conditions, for at least 24 hours, preferably 2 days, more preferably 5 days and most preferably 7 days. It will be appreciated that a balance is struck between a minimal use of polymer materials (e.g. low base weight and thickness) and satisfactory gas barrier properties.

Gas barrier can be increased a thickening of the flexible material.

Good gas barrier properties can also or alternatively be achieved by inclusion of nylon (polyamide) and/or ethylene vinyl alcohol (EVOH) in the flexible material, either as a blended component or as barrier layer within a laminate material.

Coatings

The flexible material may be coated or layered with other materials. The flexible material may be laminate constructions of a plurality of layers of similar or dissimilar films, such that the flexible materials are a composite construction.

Examples of coatings include, without limitation, polymer coatings, metalized coatings, and/or ceramic coatings. Coating materials and/or laminate constructions may reduce permeability of the inflation material stored in the inflated chambers, increase thermal insulation, reduce susceptibility to condensation build up etc. Alternatively, the coating materials may provide decorative or informative purposes.

It is also possible to improve user comfort by inclusion of perfume or fragrance additives to the flexible material, this may mask plastic smells, be associated with an event and/or influence sympathetic nerve activity, such as some believe lavender may be restful.

Skin feel of the flexible material may be improved. In this respect the flexible material may comprise, be blended with and/or be coated with enhancing powders as additives. Preferred examples include calcium powder, starch powder and/or carbon black. Such additives are comprised in an external layer of the mattress, preferably an upper external layer upon which an user may recline.

Carbon black is particularly preferred. It can be blended into a polymer such as polyethylene, particularly LDPE, as a filler, or may be coated onto a flexible material. Carbon black is particularly advantageous as it may impart electrical conductivity to the mattress surface reducing build up of static electricity, which may be unpleasant for a user. Carbon black having an average particle diameter of from 15-40 nm may be suitable. Carbon black may be included as a filler in the flexible material or in a surface zone of the flexible material at 3-15 wt % of the total of the carbon black and polymer.

Laminates

In some embodiments, the flexible sheets may be film laminates that include multiple layers of the same or different types of materials to provide desired properties such as strength, flexibility, the ability to be joined, imperviousness to inflating material, e.g. gas, and the ability to accept printing.

A preferred example of a film laminate includes a laminate comprising LDPE/tielayer/polyamide/tielayer/LDPE. A preferred total thickness is of 30-100, preferably about 60 micrometer.

A preferred example of a film laminate includes a laminate comprising LDPE/tielayer/EVOH/tielayer/LDPE. A preferred total thickness is of 30-100, preferably about 60 micrometer.

The thickness of the laminate is a balance between suitably thick to ensure a gas(air)-tight barrier and resistance to deformation under stress; and avoiding excess material and noise generation (crackling).

Mattress Material Make Up

The mattress is preferably composed of material types that are easy to dispose of, recycle or destruct. The mattress may comprise polyethylene, polypropylene, polyethylene terephthalate, polyethylene furanoate, polyester, nylon, or polyvinyl chloride. Preferably the mattress is made of polyethylene.

Preferably the mattress comprises at least 60 wt %, based on the total weight of the mattress components, of thermoplastic polymer, more preferably at least 70 wt %, still more preferably at least 85 wt %, still more preferably at least 95 wt %, and most preferably at least 98 wt %.

Preferably the mattress comprises at least 60 wt %, based on the total weight of the mattress components, of a single polymer type selected from the types polyethylene, polypropylene, polyethylene terephthalate, polyethylene furanoate, polyester, polyamide (e.g. nylon), or polyvinyl chloride. More preferably the weight percentage is 70 wt %, still more preferably 85 wt %, still more preferably 95 wt %, and most preferably at least 98 wt %.

More preferably, at least 50 wt % of the mattress is a single polymer type, more preferably at least 60 wt %, more preferably at least 70 wt %, still more preferably 85 wt %, and still more preferably 95 wt %. Preferably the polymer type is polyethylene.

It is preferable that the mattress comprises no valves constructed from plastic types different to the sheet material. Separate valves may be expensive to manufacture and incorporate, add weight to the mattress, and can be difficult to dispose of, e.g. by recycling or destruction, leading to high environmental impact. Preferably the mattress is free of valves.

It is preferable that the mattress contains a minimum of thermoset polymer materials. Preferably the mattress comprises less than 10 wt % of thermoset polymer materials based on the total weight of the mattress components, preferably less than 5 wt %, more preferably less than 2 wt %, and most preferably the mattress is substantially free of thermoset polymer materials.

Method of Mattress Production

The mattress is made from flexible polymer material, which can allow simple and cost-efficient manufacturing.

For example, the mattress can be made from continuous webs of flexible material. The webs of material may be provided from rolls of material, or by blow-extrusion as tubes, or by any other source.

This allows the mattress to be manufactured in a continuous, fully automated process in which a web of material is altered over a sequence of steps, resulting in large quantities of identical products.

Various apparatus and methods for joining flexible sheets are known in the art of sheet handling. Conventional sheet handling apparatus and methods may be used to form the mattress with structural support chambers.

An exemplary process for making a mattress discussed above, may comprise: providing a web or webs of flexible material, for example from a roll of from blow-extrusion, conveying the web or webs of flexible material along a path; and joining juxtaposed surfaces of flexible material to one another along predetermined join lines with a joining device (preferably a sealing device).

In some embodiments the juxtaposed surfaces may be opposing inner surfaces of tube of flexible material; opposing surfaces of a flexible sheet folded upon itself; or opposing surfaces of two separate and juxtaposed flexible sheets.

In a preferred embodiment joins are formed between the juxtaposed surfaces as the flexible material is conveyed along a longitudinal path of travel. The longitudinal path may be linear, non-linear, meandering or of wave form. A joining device (such as a welding head) may shift in the machine direction and/or lateral to the machine direction, to produce linear, non-linear, meandering or waveform join.

A preferred method of production comprises blow extruding a tube of polymer film;

-   -   optionally winding the tube onto a master-roll;     -   joining juxtaposed inner surfaces of the tube, preferably by         heating sealing or welding, more preferably by thermally         welding, to provide a sealed material;     -   optionally transferring the sealed material to distribution         rolls.

Inflation of the mattress may be achieved by providing pressurized gas into the inflatable chambers of the mattress, and sealing, preferably permanently sealing the periphery of the inflated chambers.

The invention is further directed to a method of manufacturing a mattress as discussed herein, the method comprising the steps of:

-   -   providing a flexible sheet of material an upper external         surface, an upper internal surface, a lower internal surface and         a lower external surface;     -   joining the upper internal to the lower internal surface in a         pattern to form a plurality of inflatable chambers.

Inflation of the Inflatable Mattress

The inflatable mattresses may be provided as inflatable webs having a pattern of inflatable chambers that can be inflated to provide gas-inflated chambers.

The inflatable (uninflated) webs can be shipped or supplied from a producer to an end user or distributor on a roll. Such a roll may have a large number of inflatable mattresses thereon (e.g. 30 or more, (see comment above)) yet still have a relatively low volume for transportation. A distributor or end user can inflate dispense the uninflated mattresses from the roll as needed and inflate them. This can be done locally to an intended area of use or in situ.

The inflatable mattresses as described herein may be reliably and consistently inflated outside a factory environment, e.g. in situ at a campsite etc. to quickly and conveniently provide bedding, while also having a relatively low environmental and economic impact.

An apparatus and process for simple and efficient inflation of the inflatable mattresses is also described. The apparatus and process can inflate the mattresses webs to provide gas inflated chambers.

As discussed, the internal surfaces of the flexible sheet of material of the inflatable mattress are joined, preferably sealed together, in a pattern of inflatable chambers.

In a preferred example, each chamber is provided with at least one inflation port located at a proximal end of each chamber

The web may also be provided with one or more longitudinal flanges that extend beyond the inflation ports and join-lines. The longitudinal flange may preferably form a manifold in fluid communication with, preferably each of, the inflation ports of at least two or more of the inflatable chambers. This conveniently allows a plurality, or preferably all, of the inflatable chambers to be inflated via a single fluid injection nozzle inserted into the manifold. This reduces or eliminates a need to separately inflate the chambers in a mattress.

A method of inflating the inflatable mattress is also provided. A preferred method comprises the steps of:

-   -   a) providing an inflatable mattress with a plurality of sealable         chambers each having at least one inflation port, and a         longitudinal flange, preferably a manifold in fluid         communication with said inflation ports;     -   b) placing a fluid injection nozzle into the longitudinal         flange, preferably manifold, the nozzle comprising a fluid         outlet port for injection of fluid, preferably gas, into the         inflatable chambers;     -   c) inflating the sealable chambers by injection of fluid from         the fluid injection nozzle into the longitudinal flange,         preferably manifold; and     -   d) sealing the inflation port of each inflated chambers.

In a preferred embodiment, the inflatable mattress and fluid injection nozzle are moved relative to each other so as to advance the fluid injection nozzle longitudinally into the manifold.

Preferably a sealing element is provided, preferably in substantially fixed relation to the fluid injection nozzle, which sealing element seals said at least one inflation port of each sealable chamber following inflation by the fluid injection nozzle.

Preferably the sealing element is in substantially fixed relation to the fluid injection nozzle. The sealing element is preferably positioned to the rear of the fluid injection nozzle's outlet in relation to the relative movement of the inflatable mattress and fluid injection nozzle.

Sealing is preferably done by heat sealing, conductive sealing, impulse sealing, ultrasonic sealing, welding, crimping, bonding, adhering, and combinations of any of these. Heat sealing is preferred.

Preferably a cutting element is provided, which cutting element is positioned to cut or slit said manifold longitudinally, allowing relative longitudinal advancement of the fluid injection nozzle into the manifold.

Preferably the cutting element is in substantially fixed relation to the fluid injection nozzle. The cutting element is preferably positioned to the rear of the fluid injection nozzle's outlet in relation to the relative movement of the inflatable mattress and fluid injection nozzle.

A suitable apparatus for inflating an inflatable mattress may comprise:

-   -   a) a mechanism for conveying the inflatable mattress along a         path of travel;     -   b) a fluid injection nozzle within the travel path and         positioned for insertion in said manifold, the fluid injection         nozzle comprising a fluid outlet port for injection of fluid         into the manifold and inflatable chambers and being adapted to         position the fluid outlet port adjacent to the inflation ports         such that as the conveying mechanism conveys the inflatable         mattress along the travel path, the inflation nozzle moves         longitudinally within the manifold to inflate the chambers         sequentially by the introduction of fluid into their respective         inflation ports;     -   c) a sealing element for sealing the inflation ports; and     -   d) preferably a cutting element for longitudinally cutting the         manifold as the inflatable mattress is conveyed along the travel         path.

Suitable inflation devices and techniques are known from, for example, patent publications US2007/0251190, EP1616693 and US2007/0011989.

Embellishment

The mattress may be readily adorned with embellishments. This is at least partly because these components comprise flexible sheet materials, which can be easily visually embellished, e.g. by printing, as conformable webs, before they are formed into the mattress components.

Visual embellishments may include indicia, graphical elements, decorative etchings, printing, lacquers, optical coatings, decorative coatings, ornamental textures, embossments, debossments, inks, and combinations of these elements. Visual embellishments refer to a visual element intended to provide a decoration or to communicate information. Examples of graphics include one or more of any of the following: colors, patterns, designs, images, and the like.

Visual embellishment may be provided to any surface of the mattress. Application of visual embellishment to an upper outer surface of the mattress may be preferred because it is this surface that is most readily externally visible.

The visual embellishment may have any of a plethora of uses, for example, they may aid in identifying a particular mattress within a plurality of many similar mattresses, aiding hygienic use, e.g. custom or unique prints for individuals may be applied; may indicate characteristics of the mattress; may refer to a brand name of the mattress supplier, mattress owner, or an event (e.g. outdoor music festival) at which the mattress is used.

Functional embellishment may include functional printed textures, printed electronics (such as Near Field Communication or Radio Frequency ID technologies), scented coatings, responsive coatings and smart coatings, including thermal chromics, temperature sensitive coatings, and environmentally responsive coatings.

Single-Use/Non-Durable

The inflatable mattress of the invention is preferably a non-durable mattress. The term “non-durable” refers to a mattress that is single-use. This is in contrast, the term “durable”, which refers to a mattress that is reusable.

As used herein, when referring to an inflatable mattress, the term “single-use” refers to an inflatable mattress that is configured to be inflated only once by an end-user. A single-use inflatable mattress is not configured for re-inflation(s) following deflation. A single-use inflatable mattress may be configured to be disposed of (i.e. as waste, compost, and/or recyclable material) following its first use. A single-use inflatable mattress may, in some embodiments, be configured to be deflatable only by a permanently damaging action, such as puncturing or slicing of the flexible sheet.

In some single-use embodiments, the inflated chambers of the mattress are permanently sealed about their full peripheries and are free of deflation openings or deflation valves.

In some single-use embodiments, the mattress may be inflatable by one or more one-way inflation openings or inflation valves, and be free of deflation openings or deflation valves.

As used herein, the term “disposable” refers to an inflatable mattress that is configured to be disposed of (i.e. as waste, compost, and/or recyclable material). Part, parts, or all of any of the embodiments of the inflatable mattress, disclosed herein, can be configured to be disposable.

As used herein the term “recyclable” refers to an inflatable mattress that comprises components and/or materials that can be reused. Preferably at least 70% by weight of an inflatable mattress is recyclable, preferably at least 80%, preferably at least 85%, more preferably at least 90%, still more preferably at least 95%, and most preferably substantially the entire mattress (e.g. greater than 97% by weight of the mattress), is recyclable. The weight percentage of the inflatable mattress that is recyclable is calculated based upon the materials entered into a recycling process, and not the yield of such a recycling process.

In some embodiments the inflated chambers of the mattress, may be sealed once inflated, such that deflation is only possible by destructive measures. Sealing may be achieved by use of a one-way valve allowing inflation but not deflation. This may aid in ensuring safe usage of mattress that is not constructed for extended usage.

After use the matrasses can be collected and deflated by destructive means. The leftover product can then be processed and recycled. The recycled material may be used as base material for new matrasses, may be chemically recycled to monomer materials.

Deflation is preferably achieved by slicing or cutting the wall of each sealed chamber of the inflated mattress, by (localized) heating or a combination thereof.

Kit of Parts

In a further aspect of the invention there is provided a kit of parts comprising an inflatable mattress as discussed in any one of more of the embodiments herein, and a pump and/or compressed gas cylinder(s) for inflation of the mattress.

Cushion Cover

The inflatable mattress may be combined with a sleeve of flexible material dimensioned to retain a head end of the inflated mattress in a pillow format. For example, a pillow may be constructed by rolling or folding a head end of the mattress at one or more flexible join lines between transverse inflated chambers. A sleeve of flexible material can be pulled over the folds or rolls to hold the pillow in place.

Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The features and advantages of the invention will be appreciated upon reference to the following drawings, given by way of example only, in which:

FIG. 1 shows an inflated mattress in perspective;

FIG. 2A-2C show an inflated mattress in perspective with headrest;

FIG. 3 is a side elevation of the inflated mattress of FIG. 2A;

FIG. 4A is a plan view from above, of the inflated mattress of FIG. 1 ;

FIG. 4B is an enlarged partial view of FIG. 4A;

FIG. 5A is a plan view of an uninflated mattress of FIG. 1 ;

FIG. 5B is an enlarged partial view of FIG. 5A;

FIG. 6 illustrates an inflation step of uninflated mattress of FIG. 4 ;

FIG. 7 illustrates a longitudinal cross-section through a number of inflated chambers of the mattress; and

FIG. 8 shows a schematic view of a production device and product step.

DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The following is a description of certain embodiments of the invention, given by way of example only and with reference to the drawings.

Referring to FIGS. 1 to 4 there is shown an inflatable mattress 2 in its inflated state. The illustrated mattress 2 is comprised of a tube of flexible material 4.

In plan view, the mattress 2 is substantially a rectangle, although other forms, such as (elongated) hexagon, other polygon, or curved sides, may be used.

The mattress 2 of FIGS. 1 to 4 has the general dimensions of a single person mattress. Mattresses of greater or lesser dimensions are also contemplated.

The flexible sheet material 4 comprises an upper outer surface 18 upon which a user may lie and a lower outer surface 24, which contacts a supporting surface under the mattress 2 during use.

In FIG. 1 the inflatable mattress 2 has lateral elongate inflatable chambers 6. The illustrated elongate inflatable chambers 6 are directly adjacent one another and are provided in the full length of the mattress. Inflatable chambers 6 elongate in the length of the mattress 2 may also be used but are less preferred. Other chamber 6 patterns for the mattress 2 may also be used.

In FIG. 2A the inflatable mattress 2 is folded or rolled at a head-end to provide a pillow 8. Flexible joining lines provided between adjacent inflatable chambers 6 aid the rolling or folding of the head-end. In FIGS. 2B and 2C a sleeve 10 is provided, wrapped about the pillow 8, holding the pillow 8 in place, and possibly also providing additional tactile comfort. In some embodiment the sleeve 10 may be dimensioned to also function as a wrap for the inflated mattress 2 when rolled for ease of user transport.

FIG. 3 is a side elevation of the inflated mattress of FIG. 2A showing the pillow 8 folded over upon the upper outer surface 18. The inflated chambers 6 are generally oval in transverse cross-section, however, other cross-sections may be implemented, such as circular or ovoid.

FIG. 4A is a plan view from above of the inflated mattress 2 of FIG. 1 showing the inflated elongate chambers 6. Each of the inflated elongate chambers 6 has sealed inflation ports 12 positioned on a long edge of the mattress 2. A opened inflation manifold 16 is also provided, as will be discussed in greater detail below. The opened manifold 16 has been opened by cutting or slicing in the length direction of the mattress 2, whereby one or more flanges remain on the long edge of the mattress 2.

The inflation ports 12 in the inflated mattress 2 of FIG. 4A are permanently sealed by a seal line 26 running along the long edge of the inflated mattress 2. The seal line 26 may be a heat seal, conductive seal, impulse seal, ultrasonic seal, weld, crimp, bond, adhesive bond, and combinations of any of these. Heat sealing is preferred.

FIG. 4B is an enlarged view of a portion of the sealed long edge of the mattress 2 of FIG. 4A. Inflation ports 12 are provided at a inflation end of the chambers 6. The inflation ports 12 are formed as narrowed portions of the chambers 6 and are arranged to accepted inflation fluid such as air. The narrowing is achieved by narrowing sidewalls 28 encroaching upon the width of the chambers 6, and also optionally by provision of an island join 38 located between the narrowing sidewalls 28.

Inflation fluid is blown into the chambers 6 and once inflated a permanent seal line 26 is applied to permanently seal closed the inflation ports 12 and the chambers 6. Deflation is thereafter possible only by destruction.

The opened manifold 16 that has been opened by cutting or slicing in the length direction of the mattress 2, initially forms a manifold 16 fluidly communicating with each of the inflation ports 12. As an fluid injection nozzle is passed into the manifold 16, the manifold is sliced or cut to allow relative movement of the mattress 2 and the fluid injection nozzle. After cutting, one or more flanges may remain on the long edge of the mattress 2.

FIG. 5A illustrates a top plan view of an uninflated mattress 2.

A pattern of join lines 14, such as heat seal lines, is provided between inner surfaces of the flexible material 4 of the mattress, forming a plurality of inflatable chambers 6 with inflatable ports 12 and an inflation manifold 16.

The uninflated mattress 2 may comprise a tube of flexible material 4 collapsed upon itself with inner upper and lower surfaces joined by joins lines 14. The uninflated mattress 2 may alternatively comprise a sheet of flexible material 4 folded upon itself with inner upper and lower surfaces joined by joins lines 14, or two or more separate sheets of flexible material 4 opposed and joined to one another.

The pattern of join lines 14 provides inflation ports 12 for each inflatable chamber 6. To inflate the mattress 2 inflation fluid is blown into the chambers 6 and thereafter, while still inflated to a desired pressure as previously described, a permanent seal line 26 is applied across the inflation ports 12 to permanently seal closed the inflation ports 12 and the chambers 6. Deflation is thereafter possible only by destruction.

The manifold 16 in FIG. 5A is formed as a tubular element in fluid communication with each of the inflation ports 12. A fluid injection nozzle may penetrate into the manifold 16 for example in an open end of the tube, and inject inflation fluid at pressure. To move the fluid injection nozzle relatively along the manifold 16 the tube of manifold 16 is cut or sliced open during or after sealing of adjacent chambers 6.

The material of the flexible sheet 4 may be any of the materials as discussed here above.

FIG. 6 illustrates a mattress 2 during inflation. A fluid injection nozzle 40 connected to a source of pressurized fluid such as air, is inserted into manifold 16 and fills the manifold with pressurized fluid. The pressurized fluid enters the chambers 6 adjacent the nozzle 40 and inflates them.

Suitable gases for inflation include air or N₂, to create tension in the flexible material 4, providing stiffened, semi-rigid of rigid cells that act as support elements for a reclining individual.

The nozzle 40 is moved relative to the mattress 2 by driving the mattress 2 rearwardly in relation to the nozzle 40. A blade 44 slices open a side of the manifold 16 as the mattress 2 and nozzle 40 are moved relative to one another, allowing progress of the nozzle 40 to inflate subsequent chambers 6.

Following inflation of each chamber 6 a permanent seal 26 is applied to the inlet ports 12 by sealing head 42, which preferably seals with heat.

FIG. 7 shows a partial longitudinal, vertical cross-section through three inflated chambers 6 of the mattress 2 of FIG. 2 . The flexible sheet material 4 comprises an upper inner surface 20 and a lower inner surface 22.

The upper inner surface 20 and a lower inner surface 22 are joined to each other in a pattern to form one or more inflatable chambers 6. The upper inner surface 20 and lower inner surface 22 opposed to the upper inner surface 18 are joined to each other along joins 14 to form the one or more structural support chambers 6. When inflated, the chambers 6 are preferably gas filled to a gauge pressure greater than 0.3 bar, more preferably from 0.3 to 1 bar.

FIG. 8 , illustrates an apparatus and process for manufacture of an inflatable mattress 2. Two sheets of flexible material 4 are supplied from any suitable source, possibly by in situ production, here illustrated as two rolls 50 of sheet material 4.

The sheets of flexible material 4 are conveyed along a path of travel and are aligned to form opposed upper inner surface 20 and lower inner surface 22. A conveying mechanism may include various conventional sheet-guide and sheet-drive devices as desired, such as guide rollers and nip rollers.

A joining device 52, in the form of a direct contact heat sealer equipped with a given mold or die selectively joins the juxtaposed upper inner surface 20 and lower inner surface 22 to one another along predetermined join lines 14. The joining device 52 may produce seals of any type that bind sheets together, such as heat seals, adhesive seal, cohesive seal, etc., with heat seals being preferred. A heat seal, or heat weld, may be formed when the upper inner surface 20 and lower inner surface 22, are brought into contact with one another and sufficient heat is applied for the substrate(s) to become molten and intermix. Accordingly, the joining device 52 may be provided with a heated surface to give selective heating of the flexible material 4. Both heat and pressure are preferably applied.

An exemplary joining mechanism may comprise a pair of sealing members that converge within the travel path to form a sealing zone. For example, sealing members may comprise a pair of counter-rotating belts or wheels.

Multiple joining devices or joining heads may be provided across the width of sheets of flexible material 4 to simultaneously apply multiple join lines 14.

In the above manner the joins 14 can be formed between the juxtaposed surfaces 20, 22 as they are conveyed along a longitudinal path of travel. The joining device 52 may laterally shift a joining head, e.g. a heating and pressure element in relation to the path of travel to produce the non-linear, meandering or wave-form joins.

In the illustrated embodiments sheets of flexible material are shown, however, a blown tube of flexible material or as a single sheet folded upon itself along a side edge may also be used.

The heat sealed flexible material 4 comprising the pattern of chambers 6 may be rolled to a roll 54 for convenient transport and dispensing.

Frangible lines may be provided at mattress lengths. The roll of inflatable mattresses may thus provide a series of readily separable uninflated mattresses 2.

Thus, the invention has been described by reference to certain embodiments discussed above. It will be recognized that these embodiments are susceptible to various modifications and alternative forms well known to those of skill in the art.

Further modifications in addition to those described above may be made to the structures and techniques described herein without departing from the spirit and scope of the invention. Accordingly, although specific embodiments have been described, these are examples only and are not limiting upon the scope of the invention. 

What is claimed is:
 1. An inflatable mattress comprising: a flexible sheet of material encompassing an inflatable interior volume, the flexible sheet having an upper external surface, an upper internal surface, a lower internal surface and a lower external surface; wherein the upper internal surface is joined to the lower internal surface in a pattern of join lines forming a plurality of inflatable chambers, each chamber having an inflation port, wherein said inflation ports are arranged to be permanently sealed once inflated.
 2. The inflatable mattress of claim 1, wherein the inflatable chambers are elongate and extend transverse across the width of the mattress.
 3. The inflatable mattress of claim 1 or claim 2, wherein said inflation ports are aligned along a long side of the inflatable mattress, preferably so that the inflation ports can be sequentially sealed by passing that long side over, past or through a sealing element, preferably wherein the seal is a seal line across a plurality of said inflation ports.
 4. The inflatable mattress of any preceding claim, wherein said inflatable chambers are adjoined by intermediate flexible portions, preferably wherein the flexible portion is non-inflated.
 5. The inflatable mattress of any preceding claim wherein the plurality of inflatable chambers are a series of at least ten adjacent inflatable chambers, each of said chambers extending across a width of the inflatable mattress, each chamber having an inflation port, and wherein the inflation ports are aligned along a long edge of the inflatable mattress.
 6. The inflatable mattress of any preceding claim wherein said pattern provides a longitudinal manifold on a long side of the inflatable mattress, said manifold fluidly joining the inflation ports of the inflatable chambers.
 7. The inflatable mattress of any preceding claim comprising polyethylene, polypropylene, polyethylene terephthalate, polyethylene furanoate, polyester, nylon, or polyvinyl chloride, preferably polyethylene, most preferably low density polyethylene (LDPE).
 8. The inflatable mattress of any preceding claim comprising at least 60 wt %, based on the total weight of the mattress components, of thermoplastic polymer, more preferably at least 70 wt %, still more preferably at least 85 wt %, still more preferably at least 95 wt %, and most preferably at least 98 wt %.
 9. The inflatable mattress of any preceding claim, wherein the inflatable mattress is non-durable, preferably temporarily reusable, disposable, or single-use.
 10. The inflatable mattress of any preceding claim, further comprising a sleeve of flexible material dimensioned to retain a head end of the inflated mattress in a pillow format.
 11. A package of at least 10 inflatable mattresses according to any of claims 1 to 10 removably wound thereon, preferably at least 20, more preferably at least
 30. 12. The package of claim 11, wherein two or more of the inflatable mattress are joined by a frangible line, for example a tearable line.
 13. An inflated mattress comprising the inflatable mattress of any of claims 1 to 10, wherein inflatable chambers of the mattress are inflated to a gauge pressure of greater than 0.2 bar up to 1 bar, preferably up to 0.5 bar, and are permanently sealed.
 14. A kit of parts comprising an inflatable mattress as defined in any of claims 1 to 10 or a package according to any of claims 11 to 12, and a inflation device, preferably a pump or compressed gas source.
 15. A method of making an inflatable mattress according to claim any of claim 1 to 10, comprising the steps of: providing a flexible sheet of material having an upper external surface, an upper internal surface, a lower internal surface and a lower external surface; joining the upper internal surface to the lower internal surface to form a plurality of inflatable chambers. 